1. Field of the Invention
The present invention relates generally to portable computers and, in a preferred embodiment thereof, more particularly relates to a portable notebook computer having operatively disposed in its base portion three drive unitsxe2x80x94a floppy disk drive, a hard disk drive and a CD ROM drivexe2x80x94in addition to an internal modem and AC/DC adapter, a dual PCMCIA card bay, and a battery.
2. Description of Related Art
Small portable computers, such as the increasingly popular notebook computer, continue to become more sophisticated, powerful and more like their larger desktop counterparts in terms of overall versatility of use. As it has evolved, the notebook computer typically comprises a generally rectangular base housing with a keyboard and pointing device mounted on its top side. A lid housing is hinged to a rear top side edge portion of the base housing for pivotal movement relative thereto between (1) a closed storage and transport orientation in which the lid extends across and covers the top base housing side, and (2) an upwardly pivoted use orientation in which a the keyboard and pointing device are exposed, and a display screen in the inner side of the lid housing faces the user of the computer.
The base housing of a conventional notebook computer is of a generally rectangular configuration and typically has a left-to-right length of approximately 11xe2x80x3; a front-to-rear width of approximately 9xe2x80x3; and a vertical thickness of approximately 1.5xe2x80x3. Compared to the volume within a typical desktop computer housing, the volume within a notebook computer base housing is extremely small. Yet it within this diminutive interior space that the various electronic components of the notebook computerxe2x80x94such as its hard drive, system board, processor and the likexe2x80x94must be operatively disposed.
Compared to desktop computers, early notebook computers were noticeably slower and had considerably less operational versatility. For example, their processors tended to be slower and their hard drive storage capacities were lower. Additionally, the conversion of AC electrical power supplied to the computer to the necessary DC electrical power for use by the computer was accomplished by a bulky exterior converter xe2x80x9cbrickxe2x80x9d which had to be carted around as a needed accessory for the notebook computer.
As computer designers became more skilled at operatively placing more components into the cramped interior confines of the notebook computer base housing, the notebook computer began to approach the desktop computer in terms of speed, capacity and operational flexibility. For example, later notebook computers were typically provided with both an internal hard disk drive, an internal floppy disk drive and, in some instances, an internal AC/DC converter. Later, as the incorporation of CD ROM drives became prevalent in desktop computers, it became desirable to also internally incorporate a CD ROM drive into the base housing of a notebook computer.
However, at this point, two things had happened which forced designers to choose between the floppy drive and the CD ROM drive for internal incorporation in the notebook computer base housing along with the internal hard drive and the internal AC/DC power converter. First, there appeared to be insufficient physical room for three drive units (i.e., a hard disk drive, a floppy disk drive, and a CD ROM drive) and an internal AC/DC converter within the interior of a standard-sized notebook computer base housing. Second, as these drive units, and the computer processor, became larger and faster, their combined operational heat outputs, coupled with the operational heat of other internal components such as the internal power converter, begin to exceed the amount of heat that could be effectively dissipated from the base housing.
Accordingly, as a compromise, notebook computers were designed to give the consumer a choice of (1) an internal power converter, hard disk drive and floppy disk drive, or (2) an internal power converter, hard disk drive and CD ROM drivexe2x80x94in other words, only two internal drive units and an internal power converter. If the consumer ordered the internal floppy disk drive, and also wanted a CD ROM drive, the CD ROM drive had to be an external drive unit. On the other hand, if the consumer ordered the internal CD ROM drive and also wanted a floppy disk drive, the floppy disk drive had to be an external drive unit.
However, particularly to more sophisticated consumers having all three drive units in their corresponding desktop computer, this compromise is not satisfactory. Accordingly, a need exists for a portable notebook computer capable of internally incorporating in its base housing portion (1) a hard disk drive, (2) a floppy disk drive, (3) a CD ROM drive, and (4) an AC/DC power converter. It is to this need that the present invention is directed.
In carrying out principles of the present invention, in accordance with a preferred embodiment thereof, a portable computer, representatively a notebook computer, is provided which comprises a base housing having top and bottom sides, and a display screen housing secured to the base housing for movement relative thereto between open and closed positions.
First, second and third drive units, an AC/DC electrical power converter and a processor are mounted within the base housing. Representatively, the first, second and third drive units are respectively a CD ROM drive, a hard disk drive, and a floppy disk drive, with the hard disk drive being preferably mounted in a vertically stacked relationship with the CD ROM drive. Illustratively, the base housing is formed from separable top and bottom sections, with the hard disk drive being carried in an open-bottomed well portion in the top base housing section, with a heat spreader plate structure being positioned between the hard disk drive and the underlying CD ROM drive.
The processor and the AC/DC electrical power converter are adjacent one another within an interior portion of the base housing, and a cooling system is provided which is operative to create within this interior base housing portion a localized flow of cooling air which passes (1) into the base housing, (2) through the interior base housing portion and along the processor and the AC/DC electrical power converter structure and then (3) outwardly from the base housing.
Preferably, a modem and a PCMCIA card bay structure are also positioned within the same base housing interior portion as the processor and AC/DC converter, and are cooled by the same localized flow of cooling air. According to another aspect of the invention, a bottom side portion of this interior base housing portion is defined by a heat spreader structure which is in thermal communication with the AC/DC power converter structure. In accordance with another feature of the invention, a first battery is operatively disposed within the base housing, and the third drive unit is selectively replaceable with a second storage battery.
The processor is representatively mounted on a horizontally disposed circuit board that overlies the AC/DC power converter, the modem and the PCMCIA card bay structure. Top and bottom heat sinks are respectively mounted on the top and bottom sides of the circuit board and are in thermal communication with the processor. According to another feature of the invention, in a preferred embodiment thereof, the cooling system includes an axial fan mounted in the interior base housing portion and operative to create (1) a first flow of cooling air that passes along the bottom heat sink member, the AC/DC converter, the modem and the PCMCIA card bay structure and a lower portion of the fan, and (2) a second flow of cooling air that passes along the top heat sink member and through a top portion of the fan.
In one embodiment of the invention, the top and bottom heat sink members are spaced apart from and separate from the cooling fan. In another embodiment of the invention, the top heat sink member is connected to the fan, in a heat conductive relationship therewith, and the second flow of cooling passes through the upper fan portion via an opening in the top heat sink member.